Thiocarboxylate-containing hydrolysable silanes are sulfur silane coupling agents which are used extensively in rubber applications such as tires and tire components. Unfortunately, the catalysts that are used in the process of making such thiocarboxylate-containing hydrolysable silanes tend to be difficult to separate from the reaction mixture, and can at times contaminate the product or the aqueous phase containing the mixture and/or product. In addition, there still exists a need for a catalyst that can be used in the processes of making thiocarboxylate-containing hydrolysable silanes but with improved catalytic activity.